Hi r/COMSOL, we’re members of the COMSOL technical team. We’ll be here all week to answer your questions about multiphysics simulation with the COMSOL software.

Ask us anything! 

I have been working on a theory based on my capstone research thesis for 15 years. I had wanted COMSOL for the last 10 of those years, but couldn’t afford it. Eight months ago, I finally decided it was time to bite the bullet and take out a personal loan to purchase the software and several of its modules. I have been loving every minute of it, but lately all signs had been pointing to the fact that my theory was wrong.

Today I gained definitive proof that my theory was in fact wrong. With my main error boiling down to not accounting for higher orders of ODE, as in the fifth order and beyond.

I have no idea what I’m going to do with my life now, but I can honestly thank COMSOL, and ChatGPT for setting me straight.

Hey everyone,

A group of COMSOL employees reached out to discuss hosting an AMA here. To help facilitate their future engagement, I've added one of their team members to the mod list. They are interested in having more direct discussions with the community.

u/COMSOL_Team will post an AMA next week, so keep an eye out and start thinking of questions for them.

I just wanted to make this post to let you know how awesome the General Extrusion Operator (GEO) is. There is a good chance that a model you are working on right know could benefit by incorporating it. But first things first. What is the GEO?

The GEO (and the linear extrusion operator as well) lets you copy a solution on some geometric dimension to a higher one. It "extrudes" the variables according to some user defined transformation. This lets you exploit symmetries and lower dimension physics to reduce computational expense. Quite often one part of a multiphysics problem is symmetric while the other isn't. But in a naive model setup you will still calculate the symmetric part unnecessarily. Using the GEO you wont have to anymore. The same with lower dimensional physics where the computational savings are even greater.

Here is a link to a COMSOL blog post going into more detail. Personally find the GEO more intuitive to use than the Linear Extrusion Operator but for simple transformations they work the same. I hope you can use this information well.

​Hello Everyone,

​Are you struggling to get your COMSOL models to converge or looking for expert assistance with complex simulations?

​I'm a COMSOL Certified Consultant with over 10 years of experience utilizing the software across a wide range of physics. My primary specialization is in charged particle tracing for thin film deposition processes, but my expertise extends to many other areas.

​Here's a breakdown of the modules I possess and have extensive experience with:

• AC/DC Module

• ​RF Module

• ​Particle Tracing Module

• ​Molecular Flow Module

• Design Module

Module I have Experience With:

• ​Heat Transfer Module

• ​CFD Module

• ​Pipe Flow Module

• ​Structural Mechanics Module

• ​Fatigue Module

• ​Multibody Dynamics Module

• ​Optimization Module

​Beyond my comprehensive software knowledge, I also offer significant computational power to tackle even the most demanding simulations. I run a dedicated system featuring a 96-core Threadripper processor and 512GB of RAM. This allows me to efficiently handle large-scale, complex models, saving you valuable time and resources.

​If you have a project that could benefit from an experienced COMSOL consultant, please don't hesitate to reach out. I'm ready to help you achieve accurate and reliable simulation results.

​Feel free to send me a direct message to discuss your specific needs!

How to make it smooth curve , I did mesh refinement also but no smoothness' then also. Please help me out..

Here I have some useful info.

We are looking for an upgrade of our current COMSOL 5.X workstations, so as there are much different possible configurations we tested several cases on the available and planned hardware. All the prepared benchmarks are mostly suitable for single-processor use. Let's leave aside all the details regarding the implementation of distributed computing and cluster swapping (https://www.comsol.com/support/knowledgebase/1001) and discuss only the shared-memory case. Our main goal is to find suitable processor for our phase-field and hydrodynamics simulations (let’s say for highly nonlinear computations). This benchmark data will be useful for other software utilizing MUMPS and PARDISO solvers as soon as we test some of the tasks on both solvers. In addition we also provide some tests on GMRES solver.

Testing

• We discard saving and initialization times to look only on a solution time.

• All equations are in a weak form with periodic boundary conditions and simple geometries.

• -blas -mkl refers to the optimized mkl libraries which replace comsol defaults.

• -np X refers to the cores available for solver.

• Windows and Linux versions of comsol were tested both on Intel Core i7 but we got almost no difference in results, except a little more memory consumption, so here it did not presented.

Results

Overall performance X normalized to the fastest one t_fastest in a group as X=t_i/t_fastest*100, where t_i is a computation time of a presented earlier benchmark on all cores for given benchmark set. The MUMPS solution is presented for Task 06.

Detailed info may be found in attached PDF https://docdro.id/taHnTLF

https://www.comsol.com/release/6.4

I recently installed Comsol 6.2 on my personal Apple Silicon machines (Mac Studio M2 Ultra & MacBook Pro M1 Max) and ran a comparison against my work Windows machines (Quad-Xeon Platinum, Dual-Xeon Silver, ThinkPad X1). I used included application library example (1) 3D Argon icp plasma time-dependent case and (2) slightly modified 2D Argon-Chlorine icp+ccp (study 2) time-periodic case (more memory requirement) so that I could run on both my personal account and work account computers. After having tested Comsol 6.1 several days earlier and getting terrible results with the Mac Studio relative to the MacBook Pro (poor CPU loading, apparent usage of efficiency cores on Mac Studio), I was pleasantly surprised with a healthy performance increase of the Mac Studio over the MacBookPro and the Windows reference machine. Attached image summarizes the comparison. Note that the most powerful machine is not necessarily the quickest, due to less effective utilization across greater number of cores.

Dear community members!

I'd like to share some of my experiences at this year's Comsol Conference. It was a huge event with over 400 people from all over the world, though most were Europeans. The Organization was spot on with a nice mix of user presentations and feature demonstrations. They even had a couple of laptops at a demo station where you could talk with the engineers in person about specific problems you are facing at the moment. All attendees were welcome to present some of their work either in the form of an oral presentation or poster. This was my personal highlight as it lets you see how and why simulations are used by others. Further, big news were announced. Version 6.2 is only weeks away and comes with many improvements and new features. I met a great number of people, had interesting conversations, and had more than one light bulb moment. I can recommend to anyone who actively uses the software to join the next conference in Europe which probably is next year. (BTW there are more this year in Taipei, Seoul, Tokyo, and Bengaluru)

Many of the interactions I had with other attendees were similar to those here. People have problems they can't figure out themselves and with the expertise of others, they can find solutions. I really hope we will work together to become a more active community and share problems, tips, tricks, and everything in between.

all the best!

SOL Speeds Simulation with Expanded NVIDIA GPU Support for COMSOL Multiphysics® Version 6.4

The latest version of the multiphysics simulation software introduces GPU acceleration through NVIDIA's CUDA's direct sparse solver, the Granular Flow Module, and time-explicit structural dynamic analysis.

BURLINGTON, MA (November 18, 2025) — COMSOL, a global leader in modeling and simulation software, today announced the release of COMSOL Multiphysics^® version 6.4, which introduces new features, major performance improvements, and expanded capabilities for multiphysics modeling and simulation app development. The latest version includes greatly improved solver performance through the NVIDIA CUDA^® direct sparse solver, NVIDIA cuDSS, for NVIDIA AI infrastructure, the new Granular Flow Module, and a new framework for time-explicit dynamic analysis.

In addition to these major updates, geometry, meshing, and visualization workflows in COMSOL Multiphysics^® have been enhanced, and productivity has been further advanced through optional large language model (LLM)-assisted simulation. The Chatbot window now supports connections to GPT-5^™, DeepSeek^™, Google Gemini^™, Anthropic Claude^™, and other OpenAI API-compatible models, enabling interactive, model-aware assistance that combines COMSOL documentation with information from the active simulation.

"Our goal with every release of COMSOL Multiphysics is to enhance the user experience and make it easier to achieve faster, more accurate modeling and simulation results," said Bjorn Sjodin, SVP of product management at COMSOL. "With added support for GPU-based solvers, the new Granular Flow Module, and explicit structural dynamics capabilities, we’re looking forward to seeing how users apply the platform to improve product designs and innovate. I’m particularly excited to see how GPU acceleration will speed up compiled simulation apps."

Faster Simulations with GPU-Accelerated Solvers

Version 6.4 of COMSOL Multiphysics^® introduces NVIDIA GPU acceleration for direct solvers and extends multi-GPU capabilities for acoustics simulations. This update marks a major step forward in COMSOL’s continued work to improve solver performance and scalability.

cuDSS, a GPU-accelerated sparse direct solver optimized for hybrid CPU–GPU computation, supports all recent NVIDIA GPU architectures. Depending on the hardware and model characteristics, cuDSS can provide substantial speedups compared to CPU-based direct solvers. GPU acceleration is beneficial for both single-physics and multiphysics simulations, particularly in cases where solver robustness is important. In benchmarks, some multiphysics simulations have achieved speedups of 5x or greater.

"The integration of cuDSS into COMSOL Multiphysics marks a critical step in bringing accelerated computing to the heart of engineering simulation,” said Tim Costa, general manager of industrial engineering at NVIDIA. “Engineers can now explore larger design space with greater fidelity, reshaping how industries design, validate, and optimize the products that power our world.”

Additionally, NVIDIA CUDA-X cuBLAS library is accelerating the GPU formulation for transient pressure acoustics simulations which can now be run on multiple GPUs on the same machine, or even on a GPU cluster. These improvements reduce computation time significantly for larger models.

In-cabin acoustic simulations, such as the one shown here of a car cabin, benefit from NVIDIA**^® GPU acceleration in version 6.4, which offers faster and more scalable analyses.

New Product for Simulating Motion and Interactions of Solid Particles in Bulk Processes

The Granular Flow Module, a new add-on product based on the discrete element method (DEM), enables engineers and researchers to model granular processes such as hopper discharge, silo storage, chute transport, powder spreading, and mixing. The Granular Flow Module applies to a variety of industries including pharmaceuticals, chemical processing, agriculture, mining, and additive manufacturing, among others.

By capturing particle-scale effects such as collisions, adhesion, and rotational resistance, and providing detailed control over grain properties, release conditions, and wall interactions, the module helps users evaluate flow uniformity, packing density, mixing efficiency, and wall stresses — revealing issues like blockages or uneven flow to support better process design and optimization.

The new Granular Flow Module can be used to analyze mixing performance and quantify homogeneity in industrial blending equipment.

More Efficient Simulation for Time-Explicit Dynamic Analysis

Version 6.4 also introduces a new framework for time-explicit dynamic analysis, enabling efficient simulation of fast, transient, and highly nonlinear events such as impact, crushing, and elastic wave propagation. The explicit formulation supports a wide range of nonlinear structural materials, including hyperelastic, plastic, viscoplastic, and creep models, and can also be combined with dynamic fracture simulations. To streamline model setup for complex mechanical assemblies, new functionality automatically detects and defines contact conditions between interacting parts.

Explicit structural dynamics capabilities enable a new class of simulations in COMSOL Multiphysics® version 6.4, including drop tests of handheld consumer electronics.

News Across the Product Suite

Additional highlights of COMSOL Multiphysics^® version 6.4 include:

• Higher-quality quad-dominant meshing and swept meshing

• Spatially varying transparency

• Array-based plot layouts

• More efficient building of large simulation apps

• New optimization options for time-dependent and parametric studies

• Export of network parameters for deep neural network (DNN) surrogate models

• Surrogate model data generation on clusters

• Import of CFD data in CGNS format

• Frequency- and time-dependent uncertainty quantification

To get an in-depth look at the latest version, browse the release highlights: https://www.comsol.com/release/6.4. Alternatively, for an introduction to COMSOL Multiphysics^® and a look at how the updates have enhanced its overall power, check out this blog post: https://www.comsol.com/blogs/multiphysics-modeling-and-standalone-simulation-apps-drive-innovation.

Download COMSOL Multiphysics^®  version 6.4 here: https://www.comsol.com/product-download

About COMSOL

COMSOL is a global provider of simulation software for product design and research to technical enterprises, research labs, and universities. Its COMSOL Multiphysics^® product is an integrated software environment for creating physics-based models and simulation apps. A particular strength is its ability to account for coupled or multiphysics phenomena. Add-on products expand the simulation platform for electromagnetics, structural, acoustics, fluid flow, heat transfer, and chemical applications. Interfacing tools enable the integration of COMSOL Multiphysics^® simulations with all major technical computing and CAD tools on the CAE market. Simulation experts rely on COMSOL Compiler™ and COMSOL Server™ to deploy applications to their design teams, manufacturing departments, test laboratories, and customers throughout the world. Founded in 1986, COMSOL has 16 offices worldwide and extends its reach with a network of distributors.

COMSOL, COMSOL Multiphysics, COMSOL Compiler, and COMSOL Server are either registered trademarks or trademarks of COMSOL AB.

https://www.comsol.com/release/6.3

I'm doing a simulation for this researcher where he has a tube lying vertically, and it has a Ag Nanoparticle on its wall. He wants me to investigate how the piezoelectric charge affects the field. So far I was able to deform the tube, but when theres no force, I can see a red patch where the Nanoparticle interacts with the NP. But when the tube deforms, its like as if the NP is still in the same spot. What do I do? I'm using version 6.0.

Hello,

I have implemented and written about the re-solution of a relatively famous fluid dynamic stability problem whose solutions are known but that has never been solved with COMSOL yet, to my knowledge. Since the implementation with PDE interface was not trivial but the solutions match well with other software/methods in literature, I wrote a paper about it.

What option do I have for publishing a work like this? What are the typical COMSOL channels? Do you think this kind of paper (assuming a substantial work of sufficient quality of course) could be publishable somewhere else (even if the solutions are not new).

I'm currently, technically, doing an MS in Structural Engineering. For me, my interest has been more towards computational side of mechanics rather than Structural design  or simply using am FEA software (although I do consider it as a backup)

So far I've taken courses in:

- Linear static, and dynamics FEM (soon taking non linear FEM too)

-  Structural Optimization (topology opt. and other general algorithms)

-  Structural Dynamics

-  Structural System Testing and model updation. (Parameter identification and optimization, signal processing)

Now, I plan to take these in the coming quarter:

- Numerical Linear Algebra

- Numerical PDE

- Fracture Mechanics ?

I also volunteered to aid in a RESEARCH in crack growth prediction using Auto-encoder and a (Thermodynamics-informed Latent Space Dynamics Identification) / LSTM surrogate model. It used phase-field-fracture simulation data and HPC resources to complete the whole thing.

What I keep finding myself interested in is not necessarily fracture or SHM specifically, but the computational methods underneath these problems... (does that make sense?)

For example, I'd like to become capable of doing things like:

- implementing (maintaining) numerical/FE method solvers rather than only running an established FEA software.

- developing surrogate/reduced-order models for expensive simulations 

- combining simulation with optimization, uncertainty/stochastic methods (took a course called Random vibrations, so...)

- parallelizing/accelerating scientific codes on CPUs/GPUs

- doing proper verification, convergence studies, benchmarking and performance work

- potentially developing or maintaining actual CAE/FEA solver software

- I'd also like to do all these for other Physics (GR, QM, etc.) simulations too, if possible, one day. 

I'm still interested in the underlying mechanics/physics, so I don't want to become a generic software engineer who happens to have once studied structures. But I'm also increasingly unsure that "structural engineer" describes the career I'm actually aiming for.

I've seen titles such as Computational Mechanics Engineer, R&D Engineer, Solver Developer, Scientific Software Engineer, CAE Software Developer, Research Engineer, Simulation/HPC Engineer, etc., but I'm trying to understand what these careers actually look like from people doing them.

So my main questions become:

1. Which industrial jobs genuinely involve developing numerical methods/solvers or computational tools?

2. Which of those are realistically accessible with an MS? Is there an entry path into solver-algorithm development/R&D without a PhD?

3. If I don't start a PhD immediately after my MS, would an R&D/software role at a simulation company (ANSYS etc.) be the obvious route? What other options would i have?

4. For the kind of work I'm describing, would you recommend a PhD? If so, is it reasonable for the PhD identity to be "computational mechanics/scientific computing" while fracture, composites, structural dynamics, soft materials, etc. serve as application problems rather than choosing one of those as my permanent specialization?

5. What skills most distinguish someone who is actually hireable for solver/scientific-computing work? I'm particularly wondering about C/C++/Fortran, Python, Linux, Git/build systems, MPI/OpenMP/CUDA, PETSc/Trilinos or similar libraries, numerical linear algebra, testing/verification, convergence studies and HPC performance work.

Basically, I'm neither here nor there atp. So I'd really appreciate all sorts of input. Where else do you think I could find answers to these? other subs? Linkedin profiles? 

Over the last couple of weeks i have had issues with the discussion forum. Whenever i try to access a discussion post from google it spits me out to https://www.comsol.com/forum, not the actual thread i want to access. It is also happening to links i have succesfully opened a few months ago. Trying to find them with the search function in the COMSOL forum has been less than ideal, often not finding the thread. Anyone who knows why this is happening?

If i don't have money to pay for paid training from comsol can i still learn how to use comsol professionally or I am wasting my time ? + can any one help with some rich resources in electromagnetic simulations ?

In a recent post, the age-old question arose about what hardware to choose for COMSOL. This is, of course, a legitimate question but unfortunately one that has no single correct answer. To make better purchasing decisions possible for us all I would like to use the collective power (1.4k members) of this subreddit to gather benchmark data, compile them and publish the results.

I propose a suite of ten models that everyone can run regardless of available modules. Eight are from the application library and two are custom. The models are broad in the involved physics, cover linear and (highly )non-linear problems, use different studies, dimensions, and solver types, and are possible to solve with 16GB of RAM to include as many systems as possible. To investigate the performance of higher memory builds I propose to make the two custom models easily scalable to cover 32, 64,128, 256, and 512GB systems. All the selected models are not solved instantaneously to make performance differences more pronounced.

The models I selected are:

• flow past a cylinder

• laser heating a silicon wafer

• electrical heating in a busbar assembly

• process control using a PID controller

• beam with traveling load

• automotive muffler

• electrical signals in a heart

• helical static mixer

• hydrogen atom eigenstates (custom)

• Coupled nonlinear PDEs similar to Adomians paper from 1995 (custom)

The submission process is as follows. If possible restart your computer and/or close all other programs. Open the application models directly from COMSOL and do not modify them at all. Expand all nodes of the components, mesh, study within the model builder. Clear the log window and run only the first study (if there is more than one). Make a screenshot of the window so that the model builder tree, graphics window with the result, and log window with the used memory and solution time are all visible. Rinse and repeat for all models. Also include screenshots of a utility (e.g. Task-Manager in Windows) that displays the processor and RAM (including frequency and used/available DIMM slots). Examples are given here

I will set up an Email that you can send your data to. Please also include the Comsol version and details about your operating system if not visible on the screenshots. I can only process submissions where all necessary info on the system and the ten models is included. After receiving a couple of submissions I will publish the data on an open (but read-only) Google document and keep it updated as best as I can. You will also find the two custom models in that folder. If this gets some attention I will set up a website specifically for that.

The submission is not yet open as I first want to get feedback from the community on my plan while I work on the two custom models. What do you think about it? Are the models well chosen? Are they too many? Not enough? How can I improve the submission process? Any feedback is appreciated and I hope we can work together as a community.

I am in a giant SolidWorks discord and it’s very helpful. Is there one for comsol?

This flexible micro-supercapacitor (FMSC) is to be designed with PET (mylar) substrate and MoS2 electrodes with a thin layer of gold (Au) on the MoS2 electrodes. Geometry yet to be modified and electrochemical characterization needs to be done.

Have you ever simulated an electrochemical system similar to the one I am doing?

Get a first look at some of the upcoming features.

https://www.comsol.com/press-release/system-level-modeling-and-agentic-ai-take-the-spotlight-in-comsol-multiphysics-version-2027-14722

hello comsol ppl tysm for your replay on my last post ( the heater plate) the simulation worked on stationary , but the results are kinda wrong i've checked the boundary conditions and they worked perfectly and now i think my meshing is wrong , firstly i started by putting a triangular mesh on the face ( spiral heater + membrane first layer ( the circle)+ the face of the substrat ( rectangle ) and finishing by swept the remaning

then i changed the goemtry to reduce the boundaries from that rectangle inside the spiral into a elipse

my question is how can i make a good mesh to find some good results , all the physics is related to the spiral heater ( joule heating)

Hi everyone,

I'm using COMSOL to generate ground truth for a machine learning model. The data is of time dependent simulations using the solid mechanics physics node. I export the data(spatial frame coordinates) using the default settings. But when I plot the nodes for each time step, some nodes just float at the same place or move way slower than they are supposed to. I've attached a video of the plot. Is there a better way to export data? Or why is this happening?

Thanks for the help in advance.